Speakers
Description
The focus of this work consists of thermal quality control of the TB2S ladder structures for the future CMS tracker, currently in construction for use in the High-Luminosity Large Hadron Collider (HL-LHC). Efficient and reliable cooling is crucial to ensure proper functioning of the tracker in the HL-LHC conditions, throughout the detector lifetime.
Production and QC of the TB2S ladders is done in collaboration between CERN, Pakistan institutes (NEW-2 and NCP) and IPHC Strasbourg. At CERN, a testing campaign has been conducted to validate the thermal performance of the first production ladders. The tests were done with two-phase CO₂ coolant in final operating conditions of −35°C and 12 bar. The main purpose of this test campaign was to verify the thermal performance of the ladders under final operating conditions, and to identify potential anomalies. Furthermore, these tests provided key feedback to improve the production QC tests that shall be done on all produced ladders.
The presentation describes the methods and the test setup used at CERN to measure the thermal performance with CO₂, using dummy heaters in place of real detector modules, and to compare results with those obtained with water cooling at the ladder production site in Pakistan.
The study continued by cross-checking the dummy-heater results against tests done with real detector modules performed in collaboration with IPHC Strasbourg and KIT. These tests confirmed that this QC measurement method with dummy-heaters provides the needed information on the cooling quality of the produced ladders. Finally, using the overall dataset, a thermal quality control method and flowchart was established to identify potentially anomalous ladders before their integration into the new CMS tracker.